The invention relates to an OCDM system and is based on a priority application No. EP 01440370.3, which is hereby incorporated by reference.
Coding filters are used at network terminations. Splitters are used within the network.
It is an object of the invention to provide an easier and more efficient coding for OCDM signals.
Coding splitters combining both coding and splitting functions are provided.
The coding splitters themselves can be made from cascaded Mach Zehnder (MZ) filters which are located somewhere in the network and which can be integrated using planar waveguide technologies. Each OCDM transceiver as well as the network is connected to the splitter via a pair of fibres for the two transmission directions. This set-up has the advantage that the same splitter can be used for both directions to and from the transceivers on one side and to and from the network on the other side.
The inventive bidirectional coding splitter for OCDM signals includes two optical coding filters having different OCDM codes and being connected to a third optical coding filter having an OCDM code being different from the OCDM codes of the two optical coding filters or via an optical coupler, one port of each of the two optical coding filters being used to transmit signals and a respective complementary port being used to receive signals, and a third port of each of the two optical coding filters being used to transmit and receive signals to/from the third optical coding filter or the optical coupler.
The inventive bidirectional coding splitter advantageously includes the three coding filters being MZ filters and/or Fabry Perot filters, and each of the two coding filters having a lower filter parameter value than the filter parameter value of the third coding filter.
The inventive bidirectional coding splitter advantageously includes the three coding filters being reconfigurable and/or tuneable, e.g. telemetrically.
The inventive complex bidirectional coding splitter for OCDM signals includes two inventive bidirectional coding splitters and an optical coding filter or an optical coupler being connected to both bidirectional coding splitters.
Fewer components are needed.